Periapt
by Fentir
Summary: Let's see what happens when Rin finds a weird artifact and the brothers learn something they weren't prepared for. [Might contain swearing.]
1. Chapter 1

**Chapter 1: Demon**

* * *

One of these weird days, Yukio was gonna lose it.

With a sigh he shoved the glasses back up his nose, trying to stay calm. This wasn't even new; with mild surprise he found he'd gotten used to the chaos that circled around his brother like earth around the sun. Unable *not* to happen when he was around.

So when he found the classroom in ruins, he tried telling himself that it wasn't neccessarily his fault, despite him being in the middle of the situation again, a suspicious circular space around him that somehow got spared from becoming wasteland. His classmates wore looks between shock and anger on their faces, but neither was directed at Rin, which made it even more peculiar. They had surrounded him, back to back, looking for something that probably had been here a few moments ago, likely when the room still had been like Yukio had left it yesterday.

The teacher announced his presence with a cough and all eyes turned on him.

"Where the hell have you been, Yukio?"

Rin stared at his brother, who blinked in surprise. Not at the rude addressing (he couldn't get into his brother's head to use his proper title as "teacher" or "sensei" while in class) but for being glared at.

"What do you mean, Okumura-kun, I'm well on time."  
"Yeah, right on time alright.. Look, we need a new classroom."  
"I can see that. Mr Pheles will not like this.."  
"I couldn't care less what that clown thinks"  
"Well, you should, he's the director after all."

Konekomaru decided to intervene, seeing their talk wasn't going anywhere.

"Okumura-sensei, Rin is right. We came in here earlier and were attacked by coal tars.. lots of!"  
"One black cloud", Suguro added and everyone nodded agreement.

"They're coming from somewhere. And they're more aggressive than usual. How are we supposed to learn in here?", Konekomaru finished, looking at the teacher, waiting for an answer. Said youth looked at the room's ceiling, seeing how the students were right. In fact, he could see new coal tars already forming. In a couple of hours, the place would swarm with the little demons again. If they were actually dangerous, it was just a matter of time until someone got seriously hurt.

They couldn't keep fighting them in mid-class either.

"Fine. Let's do a field trip today. I will talk to Mr Pheles about this later."

* * *

"I don't like this."  
"What, Bon?"  
"Every time we do some 'spontanous field trip' it ends in a disaster."  
"Don't be so pessimistic."  
"It's not pessimism if it's true"

Shima grinned. It wasn't like Suguro to be this grim. In one way, he wasn't exactly wrong. Their rate of skidding right into trouble was astonishingly high. And the way their day had started, chances weren't too bad everything was about to get nasty. It *always* started out almost harmless. Aggressive coal tars weren't harmless. Thinking about it, Shima knew why Bon was nervous.

It would be just a normal mission, right? Knowing that, he refrained from wondering what could go wrong; just this one time, hoping it had *some* kind of influence. He looked over to the Okumuras who went ahead. Leading them, of course, the teacher. Behind him, his twin, grinning happily like some kinda psycho. The rest of them, trotting behind, Shiemi tending to her familiar, Izumo watching their surroundings with a bored expression.

Lots of forest, some lonely rocks at first. But as their group progressed further, the atmosphere changed drastically. They all felt it; someone - or something - was watching them. Wether it was a demon or something else, nobody could tell. Their previously wide-spread formation shrinked until they almost walked on top of each other, everyone's eyes on guard for danger.

"Look out", Yukio said in a low tone as not to alert the creature. "if you see anything move, tell me."

But the thing, whatever it was, didn't attack. In fact, when the group finally found and approached a cave entrance, it seemed the creature had abandoned them altogether, easing the atmosphere largely. Still, Yukio was suspicious. His brother on the other hand was the curious type and casually stuck his nose into the dark and, ignoring the teacher's nervous calls, even entered.

"Hey, look at that! I think it's a skeleton or something", Rin called from the inside - it sounded like that was pretty far in. Yukio shoved his glasses up in a gesture of forced calm. Some days he hated his brother. The elder never thought ahead before he did something, or even considered the consequences. Just plunged right into the situation, trusting in his powers to solve things. Didn't he see this would some day come back to bite him? If you let Rin do his thing, next thing they'd know would be them waiting for some rescue troup to get him out of that cave. He couldn't navigate to save his life. They'd have to go in there. Now.

Yukio felt his fists clench and unclench. Good thing the others knew about his identity by now, so they wouldn't be too shocked of what would happen next. This didn't mean he liked to ask; he never approved of his brother using Satan's powers. Anyway, there wasn't enough material around to build a torch and he didn't think to pack matches. Not much of a choice, not with Rin in there and unlikely to come out unless chased.

"Okumura-kun, care to light us the way?", Yukio called, which was answered to by silence at first, then a short "okay", a blue flash and the ground inside the cave was lighted by two rows of blue flames, one to each side. There was a curve to the right a few meters in. Yukio sighed, then nodded to his students.

"Don't wander off. Stay with the group. We'll go in."

* * *

As they delved into the cave, one thing became clear right away.

This wasn't just any, ordinary old cave. Something was.. different about it. There hadn't been warding spells, or anything protecting for that matter. Maybe some wild plants, almost hiding the entrance. But other than that.. Still it scratched Yukio the wrong way. The flames lighting the way, giving him reassurance that his brother, at least, was alright. Nothing that would ambush them as they explored this place. He did feel watched though and by the looks of the others, they felt it too.

"Yuki-chan..", Shiemi finally began in a low voice, as she stepped closer to him. "Nii-chan said someone is following us.."

The little green man nodded agreement and sqeaked as it sat on her shoulder. Yukio watched it for a moment, then nodded.

"I know. Don't worry, everything is under control."

"Under control my ass..", Suguro mumbled under his breath, but Yukio tactfully ignored him, still smiling at the insecure girl. That is, until something hit his foot as he stepped forwards, tripped him and introduced him to the hard floor. Shiemi called his name in surprise and he grunted as he pushed himself to his elbows, glaring at the object he'd stumbled across.

A skull glared back, reflecting the blue flames like a nicely polished stone. Yukio paled. Shiemi screamed, the others just stared in horror.

Something was peculiar about this skull though. Beginning from the size and weight, there were horns on both sides of its form, sharp canines and an utterly ugly crack running through the top. A demon who had lost his life to some unknown, extremely powerful hit on the head, so Yukio deducted as he picked himself up and corrected his glasses. What had that demon done here? Also; who or what had killed it? The skull was too old for Rin to have come across the living demon, even though it'd be his style; punch it until it stops moving.

As the group progressed further, they came across more skulls; but rarely any other part of their skeletons. This could either mean the demon had died too quickly or someone had seperated their head before the body died. Usually, the cut-off parts wouldn't disperse as the main bodies burned up. That's how preserved Kappa-hands still existed without evidence of the extinct species ever having been there. How or why this happened, nobody could tell. Scientists had tried figuring it out and come up with no results. Yukio explained that to his students as they walked, to keep their minds off the incredibly dense, dark atmosphere that had become even more sufficating than before.

Then; suddenly, a pained cry shuddered the air, right about the same time the flames flickered for a second. It was then Yukio started running, followed by the group. Around a corner, another, a long straight tunnel, then a large chamber. Crystals illuminated the place, providing an eerie violet colored light, being strewn across the empty space. In the midst of it, a large rock with stairs leading to the top. From below, Yukio saw a tail and a leg dangling down the upper steps; a tail he knew too well.

"Rin!", he called out, climbing the stairs in record time, finding the unconscious form of his brother lying there, holding something in his only half-closed fist. The teacher tried taking this object, but drew back his hand as something flashed at him; skin burned. Some kind of pendant, resembling the yang part of a yin-yang symbol; the material seemed to be a metal and enclosed a bright red stone where the round end of yang would be. There also was a string attached, shimmering like copper. As Yukio analysed this, the half-demon moaned and slowly came to.

"What the hell..", he growled, then found his brother staring wide-eyed at him. "Oi, Yukio."

*WHACK*

"Don't you dare doing this again!", latter snarled, hand still raised from the way he'd just slapped the blue-haired youth. "Running off like that into unknown territory!"

"What are you, my mother?", Rin snorted, sitting up and finally noticing the thing he still held, watching it with interest. "What's that anyway?"

"Seems to be a pendant of sorts"

"No way, professor Obvious."

Yukio raised an eyebrow, but decided not to grace this rudeness with an answer. Instead he further inspected the object as it was held out to him, but refrained from trying to touch it. For some reason, it didn't seem to hurt his brother, so leaving it in his hand might - as unlikely as it sounds - be the better option.

"It's a periapt, you fools", said a third voice and Rin looked up and around, trying to spot the source, making Yukio look up and frown.

"What the.. who said that?", Rin growled, standing up shakily, ignoring the increasingly worried look on his brother's face.

"Rin, there's just us.."

"Show yourself, damn it."

"Don't bother. They can't see me. Only you can", said the bodiless voice again, making Rin's tail plush itself up from the sheer surrealism of the situation. He was so much like a cat sometimes.. And like a cat, he almost hissed when from the corner of the platform, someone approached them. A short glance at Yukio revealed he really didn't see the newcomer. His eyes were fixated on Rin, wondering whatever. Maybe Yukio now deemed him insane or something. Hell, right now, Rin himself doubted his sanity, as he watched that creature come to stand before him.

A weird character. Hair white as snow, eyes a bloody red, skin a sickly violet, clothed in some weird black attire. A demon of sorts, judging by the pointy ears and teeth and sharp, long, claw-like fingernails. The demon grinned a teeth-baring smile.

"I've been waiting for you, son of Yuri. Took you long enough, actually."

"Wha..", was all Rin could utter before the demon put his clawed hand on the half-demon's chest. A bright flash, a surprised cry, a dull thud as he hit the ground for the second time that day.


	2. Chapter 2

Something was definitely off.

Rin noticed that the moment he opened his eyes. He pushed himself off the ground and took a checking look around. Almost looked like the monastery they'd grown up at, all with the little yard, fence and buildings at their proper places. But how had he gotten here? Yukio was nowhere in sight, nor any of the others. He was all alone here.

Almost.

If it wasn't for the white-haired .. someone. What was his name again?

"Call me Nox, boy", the creature said behind him and Rin span around on his heels, heart beating up to his nose. "So this is your.. graveyard? Interesting"

Nox ignored the confused looks the other gave him and started pacing. Yes.. this wasn't like the last one at all. The demon felt like grinning, but kept it to himself for now. Finally, no more darkness. No more tombstones covering the ground. No more mistletoe tree. No more masks. He'd taken it for granted that souls looked like that, but seeing this place now, he was almost relieved he'd been wrong.

"Hey boy..", he began again, quietly enjoying the harsh flinch he saw in the sanguine-haired half-demon as he spoke up. "Do you realise where we are?"

Rin shook his head, unable to form coherent words. Nox sighed. This was gonna be _soo awesome_. He'd expected the kid to snap, but this was ridiculous.

"The thing you picked up is not just a talisman. It belonged to a good friend of mine. A friend who happens to be your blood-related father."

The demon waited for a reaction other than being stared at as if he'd just grown a second head. Also, other than seeing his counterpart step back on wobbly legs and drop on his butt, eyes wide. Then he realised _what_ he'd just said and saw his mistake. Being in here allowed him to access this kid's memories and knowledge; he should've known better. Making a note to keep this in mind, Nox went on.

"No, not who people told you is your father. Even if the guy _was_ a devil in his own right.."

Rin still didn't seem to comprehend. So Nox decided to slow down a bit.

"This place is .. well. Let's call it your heart. Everyone has such a place inside them, but few ever go there. Some people have the power to come here out of their own free will. Can you follow?"

The other just nodded slowly. Alright.

"One of them was your father. He was a so-called Harmonixer, that is a person who can transform into a monster by fusing their soul with the ones they get from killing monsters. Still good?"

This time, the nod still came, but horribly delayed. Nox almost saw the cogwheels turn inside the youth's head and hear them creak from being underused.

"This talisman you got is the key to this place. Well, one key. There sure are more in the world. Every harmonixer has their own variation. My friend's aunt had this weird mirror. Her son was fond of a katana. As for my friend's father.. he owned the periapt before Yuri."

"Yuri..?", Rin whispered. He'd heard this name before. But it didn't make sense.. wasn't his mother's name Yuri? How much coincidence..

"Hah. They got it all wrong. Or maybe they bent the truth. Your mother's name Alice."

"Alice..?"

"Yeh. A good girl, if I may say. All blond and slim and pretty. She died after you guys were born. Oh, she was an exorcist too. Just so you know."

"What happened to my father..?"

"You will love this one. That Fujimoto-guy you consider your daddy killed your real father. I was there and saw it - well, more like.. Yuri used my powers at the time. Not a pleasant thing, I tell ya. Stabbed right through the heart. Yuri was dead right away. Then Fujimoto found what your father had been protecting; you and your brother. You were mere toddlers at the time. He wanted to kill you to break the bloodline, but he couldn't. Instead he decided to raise you guys as normal humans, can you imagine? What a fool.. He even sealed your fusion powers in that sword you carry.."

Rin seemed lost. At least according to the far-away gaze his eyes had taken. Nox shook his head. Oh well, enough information for today.

"I think you should go back now. Come visit any time you like - it's _your_ heart after all. Keep that periapt with you, it's more valueable than your life"

The demon nodded at the talisman Rin still held in his hand. The youth looked at it, trying to process the new information. His life had just gotten a little bit more complicated, hadn't it? Damn.

"Hey boy, see that gate?", Nox then said, pointing at the very same gate Rin had used for ages when he left the monastery for school. Rin looked that direction, then back to the demon, nodding.

"Go there. Your friends are worried. Can you hear them?"

 _Rin!_ \- Shiemi's voice.  
 _Okumura!_ \- Suguro.  
 _Nii-san..! Wake up!_ \- Yukio.

As he listened, they became even louder, repeating and echoing in his head. The distant feeling of his shoulder being shaken. Also, a dull pain on his left cheek. Absentminded he rubbed the sore spot and slowly stood, albeit without his usual grace. Confusion and exhaustion made him stagger as he neared the gate. Before he could pass though, he heard Nox again.

"Don't let them know just yet. Unless you want them to think you're crazy. Otherwise be my guest and go ahead."

"Who would believe me anyway..", Rin said, his voice quiet and shaken. Then he crossed the threshold.

Bright light blinded him.

* * *

"He's coming to!"

"Everyone get back. Let him breathe"

"Rin, can you hear me?"

Said one slowly cracked open one eye and groaned. His head felt like cottonwhool had replaced whatever was between his pointy ears. He didn't even try to use his legs; rubber all the way to the ankles. A nasty itchy feeling down his spine, along the tail; every hair stood from what he felt. At least his arms showed some enthusiasm and didn't give in as he sat up, looking around. So that Nox-guy had been right; he was back in the real world. Surrounded by worried looking friends, still inside the cave, still on that rock platform.

For a moment he wondered if all had been a weird dream, then felt the talisman in his hand. Not a dream then.

Also, his cheek still hurt. Absentmindedly he raised his free hand and touched the spot, only to find Shiemi suddenly running away, her head one red mess.

Yukio, sitting next to him, snorted with a smile as he looked after her.

"She was really worried and slapped you. Sorry, I didn't see it coming", the glasses-wearer said and offered his older brother a hand as he stood. Rin gladly took it and found it surprising he didn't fold in right away. His tail also was a lot smoother than it felt. Still, Yukio's eyes were on him.

"What happened?", the dreaded question came like a lightning bolt.

Rin found it difficult to answer the same, so he scratched his head and said he didn't remember. By the looks on his brother's face, the youth wasn't convinced, but didn't push further. Without asking he put his older brother's arm over his own shoulders and helped him down the stairs.

With that the field trip was over as soon as it began; sooner than any of them had anticipated. On their way home, Yukio noticed Rin was more quiet than usual. He tried talking to his brother, but the half-demon just avoided his questions and eye-contact until Yukio gave up. He'd drill him later, when they were alone. Maybe he was embarassed and didn't want to talk about it in front of the others.

But surely he'd open up.

* * *

When he'd dropped Rin in their common dorms, Yukio had gone to inform the director of the recent events, starting with the pested classroom. He was promised the problem would be taken care of and sent off with a smile and a wave, suspiciously quick too. As if Mephisto had something to hide - oh well, scratch that. The man _always_ hid something. In the end, it might've been him who'd organised that coal tar invasion; just his style. He'd know Yukio would take the class on a trip. But that seemed pretty far-fetched, even to the youth himself.

Frustrated he hadn't made any significant progress, he returned to the dorms.

As he entered, he found Rin sitting on his bed, staring at the pendant in his hand, as if trying to figure something out. Yukio was about to ask, when the elder was faster.

"Say, Yukio.. If I knew something, but it was totally crazy.. would you believe me?"

"Of course, you're my brother. Whatever it is, you can talk to me."

At that, the elder's eyes softened a little.

"Even if it's .. _really_ crazy?"

"Spit it out, nii-san."

Rin smiled, then shook his head. "Nevermind. Maybe I fell badly or something. Hit my head or so."

With that, he put the item into his pocket and crawled under the bed sheets, just to drop like a stone, his back to a frowning Yukio.

"Rin..", Yukio said, but the only reply was a, somewhat artificial, snore. Whatever his older brother had to hide; tonight he wouldn't get it out of him. Let him have his secrets for now then, sooner or later he'd talk. Yukio just hoped it wasn't something world changing which better sooner than later should be addressed and would get worse by his behavior. Actually, come to think of it, Rin usually behaved this way only if he was hurt and didn't want anyone to know. Last time he did that, he'd almost bled out before he'd even made as much as a sound. And even then Yukio had only gotten to him because Rin had fainted due to bloodloss.

Nii-san could be incredibly stubborn at times.

He would keep an eye on him. And don't he dare to be _not_ fine.

* * *

The next morning Yukio woke to find Rin's bed empty. Now Rin wasn't an early bird - usually. There was still a couple of hours till lessons started. Yukio decided to first complete his morning routine, then look for his missing brother. He couldn't be far after all; students of the academy couldn't just leave the town without authorised personell to open the protective forcefield. Anyone attempting would experience the same feeling as running head-first into a wall - and wear the marks to show for it for the next few days. Unless Rin had forgotten about it and tried to run away, he'd be around somewhere at least. Even if he _had_ forgotten, he'd be there and would highly likely return sooner or later anyway.

Why would Rin, of all, run away?

As Yukio progressed through his morning rituals, this question followed him. It was even still there when he approached the (new and temporary) classroom where the students already waited. To his dismay, his brother wasn't amongst the crowd. That little spark of worry started to kindle, but he tried to keep it out of his face. He could feel a small frown on his forehead tho, refusing to leave.

As they entered the classroom, with Yukio following behind everyone and closing the door as he did, he threw another glance over his shoulder, as if expecting Rin to come running at the last second.

Rin didn't.


End file.
